Marine playtime

A lone red dragon plods along an otherwise empty beach, a rope around his midsection, blushing and occasionally looking around to make sure he's alone. While it's certain he's trying to hide something, what that is may be somewhat unexpected; he's simply aroused, his sizable cock softly bobbing as he walks, from what he plans on doing soon. There's just a specific place he needs to go first...
Soon enough, he arrives to a collection of large rocks, the biggest equal in size to him and with a flat top. The dragon easily hops onto the rock, then sits down to wait, swaying his tail back and forth in nervous anticipation. A couple minutes later, he hears a familiar splash, and an even more familiar voice. "Glad you could make it this time... You have a request, I can feel it."
What had surfaced was an odd looking aquatic creature, and the dragon's best friend. Slightly rivaling his size, it has a similar appearance to a mako shark, but with substantially darker skin that borders on black, two pairs of eyes, and a photophore reminiscent of that of an angler fish. They had certainly spooked the dragon when he'd first met them, but he'd quickly grown to quite enjoy their company, eventually naming them "Lantern".
"C-can't hide anything from you, huh? Um... C-connect to my mind, and I'll show you."
"Of course." Lantern's photophore changes from its usual white to a deep purple, and the dragon feels his mind expand. Whatever Lantern's species is, it has access to psychic abilities through their photophores, enabling telepathy and a few other techniques. It had certainly taken time for the dragon to get used to having someone read his mind, and he'd sent over embarrassing things by accident, but he'd mostly gotten it down.
With the dragon's mind connected to theirs, he imagines something, letting Lantern see it: Himself extremely deep underwater with a rock tied to one of his back legs with a rope, visibly inhaling water and cumming heavily as Lantern sucks him off. The two blush at the image, the dragon significantly moreso. "W-what do you think?"
"...Finally want to go all the way, huh? I've been looking forward to this day.~"
The dragon's tail starts full on wagging, and his cock visibly throbs. "I-I really want to feel what it's like to breathe water... T-took me a while to work up the courage."
"No worries, I'll make sure you have the time of your life.~ I see you've already got the rope, I'll go grab a nice big rock." Lantern dives under again. About 30 seconds later they return, carrying a sizable rock with their fins. "Could you come here? I'll get you tied off." The dragon jumps off his own rock and takes the rope off himself, passing it to Lantern, then he nervously holds out his back left leg toward them. With surprising deftness despite their lack of digits, Lantern ties one end of the rope to the dragon's leg and the other to the rock. "Perfect... Ready to get started?"
"U-um... N-now that it's actually happening..." The dragon's nerves are getting the better of him, and he considers calling this off...
"Relax." Lantern's word worms its way into the dragon's mind as their photophore tints green, and he doesn't resist as his worry melts away. "Thanks for that... Yeah, I'm ready."
With his confirmation, Lantern picks up the rock again and starts swimming out to sea, dragging the dragon along with them without much effort.
"Oh, before I forget... Feel free to command me down there like you did a minute ago. I think that might be hot..."
"Mmh, there's things I've always wanted to do to you with that... Thanks."
Once the two are quite some distance from shore, Lantern finally stops. "This ought to be a good spot. Get your lungs ready now, soon enough your only option is gonna be water.~" The dragon nods, and starts deeply breathing. Eventually he holds his breath, and at the same time as that, Lantern releases the rock and the dragon is pulled underwater.
Some bubbles leave the dragon's nostrils as he smiles down at the rock pulling him deeper, deeper, deeper... He can't resist reaching down between his back legs and-
"Don't masturbate until the rock lands." The dragon stops short of touching his cock as Lantern swims down alongside him. "Can't have you running yourself dry before we even really start, right?" While the dragon can cum several times in a row, it would indeed be best if he held off on that for now.
To pass the time as he sinks, the dragon tests out how his mind has been temporarily altered. He tries to jack off again, but can't even touch his cock before he can't will himself to continue. Next, without that intent, he tries to just grab it, which he now can, but now he body refuses to let him squeeze it. It doesn't matter all that much; with the surface out of view and his arousal continuing to build on its own, the dragon wonders whether he'll actually end up cumming hands-free.
For a good few minutes, the dragon sinks and the water pressure increases. It's far from becoming an issue, even as he passes the 400 feet mark, and he gets excited as the seabed finally comes into view, knowing the fun is about to truly start. There's a dull thud as the rock hits the bottom, and the dragon immediately starts masturbating, his mental block now gone.
Lantern settles down next to the dragon as they both sink to the seabed, the dragon sitting down. "Wish I could join you in that, but just one orgasm is enough for me, so I'm gonna save it." The dragon nods and burbles in arousal, continuing to masturbate while occasionally being commanded by Lantern.
"Drink." The dragon opens his mouth and takes a couple gulps of seawater, wincing at how salty it is.
"Exhale a little." A cluster of bubbles is puffed from the dragon's nostrils.
10 minutes underwater, and the dragon starts nearing an orgasm, now using both front paws. Happily growling out bubbles as his cock throbs harder and harder, he briefly holds back from cumming to make his climax stronger, before he lets it happen. With a pleased, bubbly roar, the dragon's cock starts pumping out cum into the water, Lantern watching as it happens. "Always forget how huge your loads are..."
After 20 whole seconds, the dragon's orgasm finally dies down, the water in front of him now a little cloudy. "Never stops being incredible... Now, how about you get some enjoyment too?"
"Go ahead! I've been working on a trick that might make that better for you, too..." Lantern rolls onto his back with his own twin claspers on display, and his photophore turns pink, a color the dragon hasn't seen on it yet. The dragon grips Lantern's claspers as he had quite a few times before, and his eyes go wide as he feels the same pleasure as if he'd done that to himself!
"If I did this right, you'll feel the same pleasure I do, and we should both cum at the same time."
The dragon smiles and nods, starting to feel just a little strain from holding his breath so long, and starts masturbating his friend. Both partners' arousal does indeed increase at the exact same rate, and the dragon can almost feel his own cock being masturbated, though he can tell it's being left alone.
Even with the dragon having climaxed not too long ago, it takes only about 5 minutes of this for him and Lantern to get close to an orgasm. "H-hey," Lantern says. "Do you want to kinda feel what it's like w-when I cum?"
"I-I'll try anything once, go for it!"
"You have claspers instead of a single penis." The dragon looks down after that, and sure enough, he's got claspers just like Lantern, though that's of course only in his own mind. It's an alien feeling, having two things down there, but being able to feel both of them throbbing in arousal, knowing both will be cumming at once soon... He's getting the feeling he'll enjoy it.
Soon, both friends are pushed over the edge, and neither hold back, both spilling cum in the sea at the same time. Lantern moans while the dragon roars again, the latter feeling even better than before as his new claspers cum heavily, his unnoticed cock being the only actual source of it.
Lantern cums for 10 seconds, and the dragon for his usual 20, before the two calm again. "Mmgh..." The dragon is now struggling with his breath, having exhaled quite a lot of air in his roars, but he's definitely still enjoying himself. "C-can't believe that's how you f-feel every time..."
"It's probably not quite the same, you cum a lot harder than I do. Anyway, you have a penis instead of claspers." With that, the dragon's crotch returns to normal in his eyes, and Lantern's photophore goes to its usual color. What definitely isn't its normal color though, is the dragon's face, now purple from his lack of oxygen. He awkwardly presses his paws to his muzzle and whines, before trying to swim up, the rock stopping him from ascending.
"Heheh, where do you think you're going?", Lantern teases, rubbing a fin on one of the dragon's cheeks. "You're staying here until you're flooded... Or maybe longer?"
"K-keep me down until I pass out."
"Perfect.~ Now, I'm just gonna relax and enjoy the show..." Lantern settles onto the seabed again, watching the dragon slowly use up what's left of his breath.
A few more minutes pass, and even though the dragon knows it's hopeless, he can't stop himself from struggling to get free, his instincts eventually driving him to try to bite through the rope-
"Leave the rope alone." He stops short just before his teeth can sink into the fibers, and gives Lantern a nervous smile. "Th-thanks..." With his face blue, he's just about at his limit, and tries to cover his muzzle again. Sinking down to sit on the seabed again, the dragon rocks back and forth a little, doing everything he can to hold on just a little longer...
"Only breathe when I tell you to." The dragon doesn't feel anything from that command, but he knows he's about to. With a whimper, he rears back as his maw opens wide... And nothing happens. He doesn't feel like anything is stopping him from inhaling, but he simply can't will himself to do so, even as his body desperately keeps trying to force him to. Repeatedly opening and closing his mouth, he whines and bubbles leave him, apparently nothing keeping him from exhaling.
As the dragon writhes in desperation, Lantern swims up to him, their photophore briefly flashing green. "Do you want to breathe?~"
"Y-yes! I don't care if it'll be water!"
"It doesn't have to be, there's an ability of mine I haven't shown you..." Lantern takes a deep breath and then exhales, and as he does a large bubble expands from his mouth. "If you can catch one of these, I'll let you breathe it, and you can breathe freely after that."
The dragon's eyes go wide, and he immediately jumps after the exhaled bubble, but it's already too high for him to reach because of the rock. He goes to bite the rope, but again is stopped by the earlier command.
"Ah, missed that one. Well, plenty more where that came from, but I'm not gonna make it easy.~" Lantern starts swimming away from the suffocating dragon, blowing another bubble every few seconds and moving fast enough that he knows the dragon can't get them. The dragon, of course, has his instincts force him to try, soon needing to pull the rock along with him.
This goes on for a couple minutes, the dragon's dwindling oxygen being continually wasted by his efforts as his body starts to tint purple from oxygen deprivation. Despite the situation, and in fact because of it, he's gotten rock hard again, approaching a third orgasm just by virtue of being so breathless his lungs are empty. Growing increasingly lightheaded, he eventually can't keep going for the bubbles any more, too weak to move the rock.
Noticing this, Lantern swims back to the dragon. "Just couldn't manage it, huh? Well, here, have a consolation prize." He blows out one more bubble, and the dragon finally manages to grab it, sleepily smiling as they inhale at last...
Before gurgling painfully as water rushes into their throat! The bubble disappears, and a phrase appears in the dragon's mind: "I can blow bubbles by deeply inhaling and then exhaling. You'll forget I told you this, but remember when you inhale." Lantern had tricked him, but that hardly mattered now... The dragon is finally drowning!
Having lungs full of water is so intensely arousing to him that he can't help but cum right then and there, thrashing and spreading it all over in an even better orgasm than the last two! As he painfully chokes, Lantern starts to suck him off, recreating the image he'd sent them earlier and starting to fill with his cum. The intense orgasm goes for 30 seconds this time, getting Lantern quite a gut, and while the flow of cum stops, the dragon's cock continues throbbing heavily as if it were cumming. Lantern moves back to simply watch after that.
Already having been so low on oxygen, the dragon's drowning doesn't take as long as it likely would have. About a minute after his first gasp, his entire body has turned a deep blue, and he sinks to the seabed, entirely exhausted and weakly breathing with an occasional hiccup. Lantern swims to him, raising his head with a fin to make sure he looks at them. "So, enjoy yourself?"
"...evvery.....sseconnd......." The dragon weakly smiles with the last of his energy, and his eyelids finally slide shut, losing consciousness at last. Lantern can feel the exact moment the dragon loses the last bit of his awareness, as well. "Now, let's get you some air..."

Some time later, the dragon starts returning to awareness and hacking up water. Seconds later, he hears "Your lungs aren't hurting.", and the pain immediately fades to nothing, now able to simply exhale the water. Opening his eyes, he finds he's back on the shore, and Lantern has flopped a bit out of the water to make sure he recovers. "You okay?"
"I-I'm fine, I think... Th-thanks, that was incredible!" Struggling to his feet, the dragon does his best to hug Lantern, wagging his tail.
"Good, good... H-hang on." Lantern gets out of the dragon's grip and flops back into the water to breathe. "Alright, brace yourself. All my previous commands are invalid."
The dragon immediately starts coughing as his lungs ache again, though it's not as bad as it had been when he woke up, and he recovers fairly quickly. "R-right, thanks. Good thinking, making that not hurt."
"I suppose that'll be it for this visit, then. Although, I'll leave you with something... When you next touch grass, you'll believe you're a quadrupedal fish and that you can't breathe air. You'll forget I told you this, but remember when you inhale water, at which point this command will become invalid." Lantern then hugs the dragon with their fins so he's not suspicious.
The dragon sighs. "See you next week, Lantern..." With that, they both go their own ways, though Lantern returns to the shore after a few seconds to watch what his command will do...
Walking away from the beach, the dragon thinks about what could be done to make next time even better, but nothing is really coming to mind. Was that the best it could get? He wouldn't really mind if that was the case... As his paw sets down on the grass, his eyes go wide as his gills flare, uselessly drawing in air! What was he doing!?
Hoarsely breathing, he bolts back for the water, already feeling his body drying up from the oppressive sunlight. Before he can quite get to the water, he trips and falls onto the sand, his face starting to go purple from the lack of oxygen. He pulls himself as well as he can, and finally manages to get his muzzle into the lifegiving water, gasping it into his... Lungs!? Lantern's last command coming to mind, the dragon raises his head as he goes into a coughing fit, getting all the water out. Once he's done, he can hear Lantern laughing... And he starts to laugh as well, already working on figuring out a way to get back at them for the prank.